Act 1
Act One begins with Strat recalling his first encounter with rock and roll ("Love and Death and an American Guitar (Strat's Soliloquy)") before his DNA froze causing him to remain eighteen forever.(In The 21/22 UK Tour This is Performed by Raven) The story is set in the dystopian city of Obsidian, once known as Manhattan. Strat and his friends who are also frozen like him: Tink, Blake, Ledoux, Jagwire, Zahara and other teens call themselves 'The Lost' protest in Falco Square outside Falco Towers ("All Revved Up with No Place to Go" / "Wasted Youth"), the residence of the tyrannical leader of Obsidian, Falco. During the scuffle, Strat's shirt is torn from his back and thrown to the ground. Falco's only teenage daughter, Raven, sneaks outside and is drawn to the discarded shirt. Picking it up, her eyes meet with Strat, but she is immediately rushed back inside by her mother and Falco's wife, Sloane. Falco himself joins the fight, throwing Tink to the ground as he was spraying graffiti on the wall of Falco Towers, so Ledoux breaks a bottle over Falco's head, giving him a facial injury.

Falco eventually drives 'The Lost' away, and returns home to Falco Towers, where Raven expresses her resentment towards him for forbidding her from ever going outside. After sending Raven to bed, Falco discusses with Sloane about how he wants to make Obsidian great again with his planned house project. However, this involves: destroying disused tunnels and subways which have become residential areas for the homeless community and 'The Lost'. They then talk about the teenagers today while lamenting their long gone youths ("Who Needs the Young?"). In her room, Raven is trying on Strat's shirt when Strat briefly climbs in and he quickly steals a magazine with her image on it. His presence startles her, but he disappears quickly just as Sloane arrives. Raven eagerly asks Sloane about 'The Lost', so her mother tells her: a chemical warfare and an earthquake occurred in this city 25 years ago. Those teenagers were trapped in a tunnel filled with poison which didn't kill them, but froze their genes causing them to remain eighteen forever. Sloane then gives Raven an early eighteenth birthday present; Falco's old biker jacket. She also encourages her to not make the mistakes she made and that she wants her to be free and to be able to fall in love.

The following day, 'The Lost' are gathered in an area of Obsidian which they call the Deep End. It is their hideaway, which is located in a disused subway tunnel nearby the 81st Street–Museum of Natural History station. Strat's best friend, Tink crashes his bicycle, then acts aggressively towards Jagwire - but the fight is stopped from escalating by Strat, who takes Tink aside, tends his wounds and tussles with him. Unbeknownst to Strat, Tink secretly has a crush on him and attempts to kiss him, but Strat pulls back. Zahara discusses Falco's house project and she also attempts to make a move on Strat which he pulls back on as well. He asks Zahara: 'on a hot summer night, would you offer your throat to the wolf with the red roses?', but this falls flat, and both Zahara and Strat are a little alienated by each other.

As Zahara leaves, she tells Strat that he needs to give up and forget about Raven, but Strat refuses. As he expresses his desire to see Raven; Blake, Ledoux, Tink and 'The Lost' briefly discuss kidnapping her in exchange for ransom. They then encourage him to pursue her romantically ("Out of the Frying Pan And Into the Fire").

Meanwhile, Jagwire pulls up on his motorbike outside of Falco Towers, after seeing Zahara there. It is briefly established that they have an ongoing unromantic relationship which is going sour. Zahara accuses Jagwire of following her and attempts to drive him away, but Jagwire persists to get his feelings through to her. Although she is aware of Jagwire's love for her, Zahara gently rejects him as she still cannot get over her first love ("Two Out of Three Ain't Bad").

Within Falco Towers, Falco and Sloane throw a party for Raven to celebrate her eighteenth birthday, much to her chagrin. Raven once again asks her father to let her explore the subways and to hang out with 'The Lost' which he bluntly and firmly refuses. Sloane attempts to brighten up the atmosphere by reminding everyone that it is Raven's birthday, but it quickly devolves into Falco and Sloane making out while reminiscing about how they got together during their wild-and-free youth ("Paradise by the Dashboard Light"). This causes Raven to leave in frustration and disgust.

In her room, Raven tearfully rips up her family photos until Falco and Sloane enter. They apologize for embarrassing her on her birthday and Zahara appears in a nurse outfit. Zahara gives Raven 'dream suppressant' medication, while Falco and Sloane tuck her into bed. Once they leave the room, Strat sneaks in through the window, and his presence soon awakens Raven, who is initially startled. Strat asks her: 'on a hot summer night, would you offer your throat to the wolf with the red roses?', but she's too busy expressing other feelings to notice the question, which disappoints Strat - who begins to leave, but she stops him. They have a heart-to-heart talk; Strat tells Raven what life is like being a 'Lost', and Raven reveals that she can never dream due to Falco making her take 'dream suppressant' medication. This leads them to serenade each other ("Making Love Out of Nothing at All") and Strat invites her to go out with him for one night. Raven agrees to go with him and just as they are about to make love, a frantic Zahara interrupts by entering the bedroom to warn them that Falco is coming, and has already invaded the Deep End. Strat then grabs Raven and they escape via her bedroom window. Outside, they are met up with Jagwire who appears with Strat's motorbike and he urges them to go just as he gets apprehended by Falco's militia. Strat takes Raven on his motorbike and they begin their escape, but Raven has second thoughts about going with him ("Bat Out of Hell"). Halfway through the ride, Raven starts fearing about what her father would do to Strat, prompting her to jump off his motorbike and run away, leaving Strat to grab the handlebars, brake and stop. Devastated and hurt, he gets back on his motorbike and zooms ahead. Strat ends up driving his motorbike at full speed, off the Atlantic Ocean cliffs when he 'misses' a sudden curve. His motorbike shatters and crushes him, severely injuring and seemingly killing him.

Act One ends with Zahara and Tink discovering his body. Zahara climbs down from the top of the cliffs and she calls the paramedics who arrive to help her carry Strat away.

Act 2
As Zahara briefly mentioned before Strat and Raven escaped, Falco was invading the Deep End. At the start of Act Two, Falco has captured many members of 'The Lost' and has confined them in 'The Vaults Of Punishment' (a cage barely big enough to hold them all) in the prison basement of Falco Towers. Falco gleefully tortures Jagwire by electrocution and Zahara appears in her nurse outfit while holding Strat's bloodied shirt. She grimly informs 'The Lost' that Strat has died just as Raven and Sloane arrive. Raven breaks down upon hearing this and is dragged away by Zahara and Sloane, leaving Falco and his militia to torture 'The Lost' ("In the Land of the Pig, the Butcher Is King"). Up in her room, Raven mourns over Strat's death ("Heaven Can Wait"). Below, 'The Lost' are still shocked to have lost their leader and they all admit that their lives are a mess - but then, their lives have always been a mess - prompting Jagwire, Blake and Ledoux to share their pasts ("Objects in the Rear View Mirror May Appear Closer Than They Are"). Having had enough of Falco's tyrannical behaviour, Sloane sneaks into the basement and frees 'The Lost' from the cage, allowing them to escape.

In the 21/22 UK Tour, In The Land of Pig is cut;Instead, Falco walks into the living room holding Strat's shirt, Raven gets mad and accuses him of killing Strat and runs to her room. Sloane tries to ask what happened and Falco says he warned Raven what would happen if she hung out with them. Then we transition into ("Heaven Can Wait") Objects is instead sung in the Deep End between Jagwire, Valkyrie, and Ledoux.

Meanwhile, Zahara takes a pint of blood from Raven and wakes her up. She tells Raven to come with her and they leave. Unbeknownst to them, Tink has been hiding in the room behind the door, and in a fit of jealousy, he violently rips into the pillows on Raven's bed - sending feathers flying everywhere - before throwing his knife at her photo. Zahara takes Raven to the safe area (script says: the attic of the Natural History Museum, but this is depicted on stage as an area filled with rocks), where she and Tink have been secretly looking after Strat who had miraculously survived his accident. She transfuses Raven's blood into Strat, enabling him to become mobile again, and he stumbles down from the rocks reciting poetry ("Teenager In Love"). Raven is shocked and overjoyed to see Strat and attempts to thank Tink for saving him, but he rudely rebuffs her. Zahara forcibly makes Tink leave with her while Strat and Raven have a heartfelt reunion ("For Crying Out Loud").

The following day, Zahara returns to Falco Towers to prepare a bag for Raven and is confronted by Falco who violently demands her to reveal Raven's location. She denies knowing where Raven is and Falco reveals that he knows that she is actually part of 'The Lost'. Sloane enters the room and she defends Zahara from Falco. She attempts to talk some sense into Falco, but he pushes her away prompting her to yell that she is leaving him. Falco is about to strike Sloane until Zahara fires two warning shots with her gun. She beckons Sloane to come with her - so they can both leave in safety.

At the museum, Strat once again asks Raven: 'on a hot summer night, would you offer your throat to the wolf with the red roses?' Raven responds to his words and happily agrees to become his, just as 'The Lost' show up. 'The Lost' become shocked and overwhelmed to see Strat alive. They joyously welcome him 'back from the dead' while serenading him with Raven ("You Took the Words Right Out Of My Mouth (Hot Summer Night)"). A 'wedding' is held - 'The Lost' dress Strat in a ruffled shirt with a sparkly silver jacket, and they dress Raven in a white dress, accompanied by a bouquet. Sloane joins in the celebration and she accepts Strat as Raven's partner. Raven throws the bouquet over her shoulder - this is caught by Zahara, who is simultaneously overjoyed and freaked out to catch it, so she throws it again - where it is caught by a female Lost member - Scherzzo(Or Valkyrie In The 21/22 UK Tour) - who gets down on one knee and proposes to Sloane.

After the 'wedding', Strat and Raven go to the Dunes where they talk - Raven reveals she is now able to dream for the first time - and they attempt to consummate their relationship. They are soon interrupted by a jealous Tink who urges Strat to send Raven back to Falco. Strat refuses, leading into a heated argument and Tink vows to get rid of Raven while lamenting his unrequited love for Strat ("Not Allowed to Love"). At Falco Towers, Falco unsuccessfully tries to dissuade Sloane from leaving him after losing Raven ("What Part of My Body Hurts the Most"), and he is left all alone to reflect on his actions. He is later visited by Tink who offers him a deal: he will take him to where Raven is, in exchange that no one gets hurt and that he will leave 'The Lost' alone after he gets Raven back. Falco becomes convinced and he agrees to the deal while amused by Tink's betrayal.

In the Deep End, 'The Lost' are gathered at the bar continuing to celebrate the union between Strat and Raven while Jagwire serenades Zahara ("Dead Ringer For Love"). Their celebration is interrupted when Falco bursts in through the wall with his militia and Tink. He reveals the deal he and Tink made and orders 'The Lost' to return Raven to him if they want him to leave them alone. Everyone resists and a scuffle ensues, which abruptly ends when Falco accidentally and unintentionally shoots Tink. Overwhelmed with shock and anger, Strat orders Raven to get away from him, prompting her to run off - heartbroken. Weak from blood loss, Tink apologizes for what he did because he only wanted to remain as they always were and Strat forgives him, telling him that he will always be his best friend and his soulmate. Tink dies in Strat's arms and 'The Lost' hold a funeral for him ("Rock and Roll Dreams Come Through"). Meanwhile, Raven is left with no choice but to return home to Falco Towers where she furiously blames her father for ruining everything.

Note: In the 2021/22 UK Tour, the book is changed so that Tink is only injured; he survives.

Six months later, Sloane is still wandering through the city, delivering a beautiful monologue about how she's tried and failed to recapture her youth. In Falco Towers, Raven has become a recluse by secluding herself in her bedroom until Strat slips in through the window. He apologizes for spurning her six months ago when he knew it wasn't her fault Tink died and that he still loves her. Realizing she is still in love with Strat, Raven rekindles her feelings for him, and so does Sloane when she returns to Falco to rekindle their marriage ("It's All Coming Back to Me Now"). Raven suddenly has second thoughts about their relationship, because after being apart for so long, she has realized that they cannot be together. When Strat asks her why, she reveals that unlike him, she is not frozen. Thus, she will age normally while he remains young forever. Strat tells Raven that he doesn't care if she gets old, because she will always be eighteen in his eyes and he will always love her no matter what.

Finale: Strat and Raven, Falco and Sloane, and Zahara and Jagwire make vows to their respective partners ("I'd Do Anything For Love (But I Won't Do That)"). During this song, Falco is forced at gunpoint into a lake by Zahara, where he emerges several seconds later dressed in a different outfit (a baptism/redemption). [In the US tour, during the song 'The Lost' surround Falco and when they disperse, he is wearing a rock style outfit.] Note: In the 21/22 UK Tour, Tink comes back for the finale, as he did not die and was merely injured, and he hugs Raven.